1. Field of the Invention
The present invention relates generally to a balance valve, and more particularly to an innovative one which is designed with an asymmetric structure to maintain cold water supply functions.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
Given the fact that conventional dual-temperature ceramic valves may lead to transient burning and scalding due to manual error in turning the faucet and the difficulty in regulating water temperature due to unstable water pressure, an improved structure of a dual-temperature ceramic valve combined with a cold-hot water balance valve (balance valve) has thus been developed in this industry.
In spite of currently available ceramic products and relevant patents based on balance valves, some shortcomings and disadvantages still exist.
A conventional balance valve generally comprises a fixed valve pipe and moveable spool. Of which, a through-hole is set separately at both ends of the fixed valve pipe, and an opening arranged separately at its both sides so as to guide cold and hot water. An inner groove is formed separately at both ends of the moveable spool, and separated by a partition. Moreover, these two inner grooves are provided with an opening connected with that of the fixed valve pipe. With this structure, when cold and hot water separately pass through two inner grooves of the moveable spool via the openings at both sides of the fixed valve pipe, the moveable spool will yield reciprocating transverse movement with the variation of cold/hot water streams' flow velocity, based on the principle of higher velocity versus smaller pressure and smaller velocity versus bigger pressure as well as the property of water flow. This will change the sectional connection area between the moveable spool and the openings at both sides of the fixed valve pipe, serving the purpose of auto balancing of cold/hot water temperature.
The following shortcomings of typical balance valve are found during actual applications:
If conventional dual-temperature ceramic valve is combined with a balance valve, the functions of full cold/hot water supply modes are not affected even if the users manually turn the faucet handle to full cold water mode or full hot water mode.
If the dual-temperature ceramic valve is switched to cold/hot water supply modes and the hot-water line is blocked due to unpredictable elements (e.g.: cracking/blocking of line, and closing of control valve), the moveable spool of the balance valve is abutted onto the hot water side of the fixed valve pipe, such that the hot water flow channel is blocked and closed. In such a case, the moveable spool and the opening at cold water side of the fixed spool are fully staggered to block off the flow channel. That is to say, when the hot water line of typical balance valve is blocked, the cold water supply functions will be lost, exerting great impact on the functionality and convenience of faucet (note: since cold water mode is a most commonly used mode).
Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products.